This invention relates generally to screen separators and more particularly concerns the structural mounts used to fix the vibrators to the basket of the screen separator.
My U.S. Pat. No. 5,683,580, which was directed to the use of non-uniform forward elliptical motion in a screen separator, summarized the use of circular, linear, unidirectional elliptical and multidirectional elliptical motion in the screen separators of the prior art. As explained in the '580 patent, the pattern of motion of a screen separator is a function of alpha, beta and epsilon angles of the vibrator shafts and the rho distance of the vibrator shafts from the center of vibratory mass of the screen separator. The structural configuration in mounting the vibrators to the basket of the screen separator does not change the motion pattern established by the above angles and distance.
A balanced or unidirectional elliptical motion screen separator is described in U.S. Pat. No. 5,265,730. A typical structural mounting configuration usable for the vibrators of a screen separator of any pattern of motion is shown in considerable detail in the '730 patent. As shown in the '730 patent, for field application separators, vibrators are normally mounted on a plate which is fixed to a tube which extends outwardly perpendicularly from the side wall of the basket of the screen separator. In some research applications the tube is replaced by a wedge block and the mounting plate fixed to the block. In either case, the vibrators are displaced outwardly from the basket side wall by a significant distance. Depending on the type of motion desired, the selected angular position of the vibrators can greatly increase their displacement from the basket side wall.
Vibrator displacement from the basket side wall induces destructive moments into the basket assembly. As a result, a heavy vibrator mounting and basket reinforcing structure are necessary which in turn decrease the efficiency and increase the cost of the separator. The greater the basket weight, the higher the vibrator settings must be and, perhaps, a larger and more costly vibrator may even be required. In addition to the induced moments problem, vibrator displacement simply results in a wider separator. This is most undesirable, especially in restricted space applications such as on an offshore rig.
It is, therefore, an object of this invention to provide an improved structural mount for a vibrator of a screen separator. Another object of this invention is to provide a structural mount for a vibrator of a screen separator which minimizes the displacement of the vibrator from the separator basket side wall. A further object of this invention is to provide a structural mount for a vibrator of a screen separator which minimizes the induced moments on the separator basket. It is also an object of this invention to provide a structural mount for a vibrator of a screen separator which is lighter than known mounts. Yet another object of this invention is to provide a structural mount for a vibrator of a screen separator which permits use of a lighter basket reinforcing structure than known mounts. An additional object of this invention is to provide a structural mount for a vibrator of a screen separator which permits use of lower vibrator settings and perhaps smaller vibrators than known mounts. And it is an object of this invention to provide a structural mount for a vibrator of a screen separator which minimizes the width of the separator.